WiringPi: Bring back all of the stuffs I removed to do with peripherals

Imported from the official WiringPi repository, version 2.60.

Signed-off-by: Deokgyu Yang <secugyu@gmail.com>
Change-Id: I82dc00ab9f038f9bc4c6a9c4ca3affe5a5d33ae1

examples/max31855.c

@@ -0,0 +1,60 @@
+/*
+ * max31855.c:
+ *	SPI Thermocouple interface chip
+ *
+ * Copyright (c) 2015 Gordon Henderson.
+ ***********************************************************************
+ * This file is part of wiringPi:
+ *	https://projects.drogon.net/raspberry-pi/wiringpi/
+ *
+ *    wiringPi is free software: you can redistribute it and/or modify
+ *    it under the terms of the GNU Lesser General Public License as published by
+ *    the Free Software Foundation, either version 3 of the License, or
+ *    (at your option) any later version.
+ *
+ *    wiringPi is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Lesser General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Lesser General Public License
+ *    along with wiringPi.  If not, see <http://www.gnu.org/licenses/>.
+ ***********************************************************************
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <time.h>
+
+#include <wiringPi.h>
+#include <max31855.h>
+
+int main (int argc, char *argv [])
+{
+  int i = 0 ;
+
+  wiringPiSetup () ;
+  max31855Setup (200, 0) ;
+  max31855Setup (400, 1) ;
+
+  for (;;)
+  {
+    if (i == 0)
+    {
+      printf ("+------+------+------+------++------+------+------+------+\n") ;
+      printf ("| Raw  | Err  |  C   |   F  || Raw  | Err  |  C   |  F   |\n") ;
+      printf ("+------+------+------+------++------+------+------+------+\n") ;
+    }
+
+    printf ("| %4d | %4d | %4d | %4d |",   analogRead (200), analogRead (201), analogRead (202), analogRead (203)) ;
+    printf ("| %4d | %4d | %4d | %4d |\n", analogRead (400), analogRead (401), analogRead (402), analogRead (403)) ;
+    delay (500) ;
+
+    if (++i == 10)
+      i = 0 ;
+
+  }
+
+}